The present invention relates to a crib having a vertically slidable drop side, and to a guiding and locking mechanism for guiding the vertical movement of the drop side and for locking the gate in a selected position.
Baby cribs typically include a drop side that can be dropped into a lowered position to facilitate placing the baby in or removing the baby from the crib, and then can be lifted to a raised position and locked in the raised position. Many different guiding and locking arrangements have been developed for guiding the vertical sliding motion of a drop side and for locking the gate in a raised position. In some prior guiding and locking arrangements, two hands have been required for releasing the locking mechanism so that the gate can be lowered. For instance, some locking mechanisms have employed a pair of spring-loaded pins fixed to the upper bar of the drop side and engageable with holes or recesses in a fixed structure of the crib. In this type of mechanism, both pins must be simultaneously disengaged from the holes or recesses in order to drop the gate, and hence two hands are required for lowering the gate. This is inconvenient when placing a baby in the crib, since one""s hands are occupied with holding the baby.
To alleviate the problem noted above, locking mechanisms have been developed that can be released by lifting the drop side upward, which can be done with one hand. For example, Australian Patent No. 107,184 discloses a mechanism for a drop side of a cot employing vertically extending guide bars affixed to the corner posts of the cot adjacent opposite ends of the drop side, and a pair of upper loops and a pair of lower loops fixed to the opposite upper and lower ends of the drop side. The loops slidably receive the guide bars. The upper end of each guide bar has a locking slot formed in its front edge to co-act with the upper loop that slides along the guide bar. Each upper loop includes an internal spring that constantly urges the loop in a direction from the front edge to the rear edge of the guide bar, such that when the drop side is raised to an upper position in which the upper loops are aligned with the locking slots, the springs force the loops into the locking slots so that the drop side is locked in the upper position. The drop side is released by lifting and pulling the drop side outwardly to disengage the upper loops from the locking slots, thus allowing the drop side to be lowered. The mechanism of Australian Patent No. 107,184 does not lock the drop side in the lowered position. The spring internal to each upper loop comprises a leaf spring having one portion that passes around and is clenched onto the upper loop and another portion that bears against the rear edge of the associated guide bar. Thus, assembly is required to incorporate the springs in the upper loops.
A number of patents, including U.S. Pat. Nos. 2,369,834 and 1,695,571, disclose crib drop side locking arrangements in which the drop side includes pins or similar projections at the opposite upper or lower ends of the drop side that extend toward the adjacent corner posts and slide within grooves or guide tracks formed in guide members affixed to the corner posts, and wherein an upper end of each guide track includes a downwardly extending hook-shaped portion that terminates at a stop or abutment at the lower end of the hook-shaped portion. The drop side is raised until the projections reach the hook-shaped portions, and is then lowered slightly so that the projections slide down the hook-shaped portions and come to rest on the abutments, thus retaining the drop side in a raised position. In these patents, there are no springs for urging cooperative locking members into engagement with each other; instead, the projections are urged into the hook-shaped portions of the guide tracks by the user urging the drop side in the direction in which the hook-shaped portion extends away from the main linear part of the guide tracks. In this sense, the drop side locking mechanisms of these patents do not automatically engage to lock the drop side in a raised position, since they require the user to produce a particular movement of the drop side inwardly or outwardly to ensure that the projections engage the hook-shaped portions of the guide tracks. Furthermore, these patents do not disclose any mechanism for locking the drop side in a lowered position.
Some prior drop side locking mechanisms, such as shown in U.S. Pat. No. 3,934,282, have employed an elongate trip wire or rod fixed along the lower rail of the drop side such that the rod can rotate about its longitudinal axis. A central portion of the rod is offset to form an actuator, and opposite ends of the rod are formed as offset cranks. In one rotational position of the rod, and when the drop side is raised to an upper position, the cranks engage stop members attached to the corner posts of the crib at each end of the drop side. The drop side is lowered by slightly raising the drop side and pressing the actuator of the rod to cause the rod to rotate such that the cranks disengage the stop members. A drawback of this arrangement is that the actuator is located at the lower rail of the drop side, and thus is in an inconvenient location for actuation by a user""s hand, and, although the user could use a foot to press the actuator; at least one hand would still be required to slightly raise the drop side. Thus, this arrangement would be awkward to use. Additionally, the ""282 patent does not disclose any mechanism for locking the drop side in a lowered position.
The present invention addresses the above needs by providing a crib having a drop side and a guiding and locking mechanism therefor, in which the drop side is locked in a raised position by sliding the drop side up until the locking mechanism automatically engages, the drop side is lowered by slightly lifting and pressing inwardly on the drop side to release the locking mechanism, and the drop side is locked in a lowered position by an additional locking mechanism. In accordance with a preferred embodiment of the invention, a crib comprises a rear panel connected between a pair of vertical rear corner posts, a front panel comprising a drop side connected between a pair of vertical front corner posts, and a pair of end panels connected between the front and rear corner posts to form a rectangular structure. The crib also includes at least one guide affixed to each of the front corner posts adjacent opposite ends of the drop side, each guide defining a vertically extending guide track. A slide is affixed to each of the opposite ends of the drop side and is in sliding engagement with the guide track of the adjacent guide, whereby the drop side is vertically slidable along the guides between raised and lowered positions. The guide track of each of the guides is formed by a pair of vertically extending, spaced guide surfaces respectively facing generally toward and away from the rear panel, one of the guide surfaces having an upper recess that is recessed in a horizontal direction near an upper end of the guide track, and the guide defining a stop surface facing generally upwardly and located adjacent a lower end of the upper recess. Each guide further comprises a resilient upper locking member affixed to the guide opposite the upper recess and arranged to contact and urge the slide into the upper recess when the drop side is slid upward to the raised position such that drop side is prevented by the stop surfaces from sliding back down to the lowered position. The slides are disengageable from the upper recesses by urging the drop side in a direction generally normal thereto so as to urge the slides against the upper locking members to deflect the upper locking members until the slides clear the stop surfaces such that the drop side can be dropped to the lowered position.
In a preferred embodiment, each front corner post has an upper guide and a lower guide affixed thereto adjacent upper and lower rails of the drop side, and there is an upper slide and a lower slide affixed to each end of the drop side for slidably engaging the upper and lower guides. The lower guides preferably have the recesses for locking the drop side in the raised position, but alternatively the upper guides could have the recesses rather than the lower guides. Of course, it is also possible to employ a single guide on each front corner post, extending from adjacent the lower rail to adjacent the upper rail of the drop side, and to provide the recess in the guide in either an upper or a lower region of the guide for interacting with either the upper slide or the lower slide, respectively.
Preferably, however, separate upper and lower guides are employed and the recesses are in the lower guides. Each lower guide preferably includes a retaining portion that projects upward from adjacent the lower end of the upper recess and forms a slot between the retaining portion and an opposing portion of the lower guide such that the lower slides cannot be disengaged from the upper recesses until the lower slides are lifted over the retaining portions. Accordingly, the drop side must be both lifted and urged in the direction generally normal to the drop side in order to be dropped to the lowered position.
In a preferred embodiment, each lower guide and corresponding upper locking member are integrally formed together as a one-piece structure. For example, the guide can be molded of plastic such that the upper locking member is integrally molded with the guide. Preferably, each lower guide further comprises a lower recess in one of the guide surfaces proximate a lower end of the lower guide, and a resilient lower locking member affixed to the lower guide for urging the lower slide into the lower recess when the drop side is dropped to the lowered position. Each lower guide defines a downward-facing stop surface adjacent an upper end of the lower recess for preventing the lower slide from being slid back up along the guide track as long as the lower slide is in the lower recess, whereby the drop side is locked in the lowered position. The guide and the upper and lower locking members advantageously are integrally formed together.
The lower locking member of each lower guide preferably is structured and arranged to apply a continuous biasing force on the corresponding lower slide when disposed in the lower recess. This arrangement can substantially reduce rattling of the lower slides on their guides when the drop side is locked in the lowered position.